Conventionally, a mobile terminal device having touch panels executes various actions by operating on display surfaces. For example, with an operation on the display surface, a page of an electronic document is turned. With a predetermined operation, a previous page or a following page of a currently displayed page is displayed on the display surface.
Besides, a configuration that a user can turn a plurality of pages with a predetermined operation performed by the user is also proposed. For example, a configuration to change the number of pages turned based on the number of fingers touching the display surface is proposed.